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991.
Priority setting for food safety management at a national level requires risks to be ranked according to defined criteria. In this study, two approaches (disability‐adjusted life years (DALYs) and cost of illness (COI)) were used to generate estimates of the burden of disease for certain potentially foodborne diseases (campylobacteriosis, salmonellosis, listeriosis (invasive, perinatal, and nonperinatal), infection with Shiga toxin‐producing Escherichia coli (STEC), yersiniosis, and norovirus infection) and their sequelae in New Zealand. A modified Delphi approach was used to estimate the food‐attributable proportion for these diseases. The two approaches gave a similar ranking for the selected diseases, with campylobacteriosis and its sequelae accounting for the greatest proportion of the overall burden of disease by far.  相似文献   
992.
Understanding patient-specific differences in risk tolerance for new treatments that offer improved efficacy can assist in making difficult regulatory and clinical decisions for new treatments that offer both the potential for greater effectiveness in relieving disease symptoms, but also risks of disabling or fatal side effects. The aim of this study is to elicit benefit-risk trade-off preferences for hypothetical treatments with varying efficacy and risk levels using a stated-choice (SC) survey. We derive estimates of "maximum acceptable risk" (MAR) that can help decisionmakers identify welfare-enhancing alternatives. In the case of children, parent caregivers are responsible for treatment decisions and their risk tolerance may be quite different than adult patients' own tolerance for treatment-related risks. We estimated and compared the willingness of Crohn's disease (CD) patients and parents of juvenile CD patients to accept serious adverse event (SAE) risks in exchange for symptom relief. The analyzed data were from 345 patients over the age of 18 and 150 parents of children under the age of 18. The estimation results provide strong evidence that adult patients and parents of juvenile patients are willing to accept tradeoffs between treatment efficacy and risks of SAEs. Parents of juvenile CD patients are about as risk tolerant for their children as adult CD patients are for themselves for improved treatment efficacy. SC surveys provide a systematic method for eliciting preferences for benefit-risk tradeoffs. Understanding patients' own risk perceptions and their willingness to accept risks in return for treatment benefits can help inform risk management decision making.  相似文献   
993.
994.
Scholars have studied how the social associations of corporate executives affect their access to information and their decisions. The entire focus, however, has been on lateral peer-to-peer associations. Prior research has not addressed vertical associations, or the idea that interaction with peer elites yields different perceptions and behaviors than does interaction with parties of lower social status. In this paper, we introduce and develop the concept of elitist association, which we define as a stable behavioral pattern of some corporate executives by which they engage nearly exclusively in associations with other elites while minimizing or even entirely avoiding associations with non-elites. We propose several individual-level antecedents to explain why some executives engage in this behavior more than others. We then discuss the effects of elitist association on executives' access to information, empathy, and social comparison processes — all of which affect their decisions and organizations. Finally, we consider implications for theory as well as for practical affairs.  相似文献   
995.
Speed is an increasingly important determinant of which suppliers will be given customers' business and is defined as the time between when an order is placed by the customer and when the product is delivered, or as the amount of time customers must wait before they receive their desired service. In either case, the speed a customer experiences can be enhanced by giving priority to that particular customer. Such a prioritization scheme will necessarily reduce the speed experienced by lower‐priority customers, but this can lead to a better outcome when different customers place different values on speed. We model a single resource (e.g., a manufacturer) that processes jobs from customers who have heterogeneous waiting costs. We analyze the price that maximizes priority revenue for the resource owner (i.e., supplier, manufacturer) under different assumptions regarding customer behavior. We discover that a revenue‐maximizing supplier facing self‐interested customers (i.e., those that independently minimize their own expected costs) charges a price that also minimizes the expected total delay costs across all customers and that this outcome does not result when customers coordinate to submit priority orders at a level that seeks to minimize their aggregate costs of priority fees and delays. Thus, the customers are better off collectively (as is the supplier) when the supplier and customers act independently in their own best interests. Finally, as the number of priority classes increases, both the priority revenues and the overall customer delay costs improve, but at a decreasing rate.  相似文献   
996.
This paper analyzes the properties of standard estimators, tests, and confidence sets (CS's) for parameters that are unidentified or weakly identified in some parts of the parameter space. The paper also introduces methods to make the tests and CS's robust to such identification problems. The results apply to a class of extremum estimators and corresponding tests and CS's that are based on criterion functions that satisfy certain asymptotic stochastic quadratic expansions and that depend on the parameter that determines the strength of identification. This covers a class of models estimated using maximum likelihood (ML), least squares (LS), quantile, generalized method of moments, generalized empirical likelihood, minimum distance, and semi‐parametric estimators. The consistency/lack‐of‐consistency and asymptotic distributions of the estimators are established under a full range of drifting sequences of true distributions. The asymptotic sizes (in a uniform sense) of standard and identification‐robust tests and CS's are established. The results are applied to the ARMA(1, 1) time series model estimated by ML and to the nonlinear regression model estimated by LS. In companion papers, the results are applied to a number of other models.  相似文献   
997.
Information about residents of institutional and noninstitutional group quarters (GQ), particularly those with disabilities, has been limited by gaps in survey data, and statistics based on data that exclude some or all GQ residents are biased as estimates of total population statistics. We used the 2006 and 2007 American Community Survey (ACS) to identify the distribution of working-age populations with and without disabilities by major residence type and to assess the sensitivity of disability statistics to GQ residence. Our findings show that (1) of those with disabilities, about 1 in 13 males and 1 in 33 females live in GQ; (2) GQ rates are higher for individuals reporting mental, self-care, or go-outside-the-home disabilities than for those reporting sensory, physical, or employment disabilities; (3) younger males with disabilities are more likely to reside there, particularly at institutional GQ, reflecting their relatively high incarceration rate; (4) individuals with and without disabilities who are black, American Indian, were never married, or have less than a high school education have higher GQ residence rates; (5) 40% of male and 62% of female GQ residents have a disability; (6) adding GQ residents to household residents increases estimated disability prevalence for males by 6%, and the estimated difference between disability prevalence rates by gender nearly disappears; and (7) inclusion of the GQ population substantially lowers employment rate estimates for young males, blacks, and American Indians.  相似文献   
998.
Bullying is a problem that affects adolescents worldwide. Efforts to prevent bullying have been moderately successful at best, or iatrogenic at worst. We offer an explanation for this limited success by employing an evolutionary‐psychological perspective to analyze antibullying interventions. We argue that bullying is a goal‐directed behavior that is sensitive to benefits as well as costs, and that interventions must address these benefits. This perspective led us to develop a novel antibullying intervention, Meaningful Roles, which offers bullies prosocial alternatives—meaningful roles and responsibilities implemented through a school jobs program and reinforced through peer‐to‐peer praise notes—that effectively meet the same status goals as bullying behavior. We describe this new intervention and how its theoretical evolutionary roots may be applicable to other intervention programs.  相似文献   
999.
Direct calculation of the non central hypergeometric (NH) distribution and its moments can present computational issues in both efficiency and accuracy. In response, several methods, both approximate and exact, for calculating the NH mean and variance have appeared in the literature. We add to this body of work, a straight-forward, exact method that is easily programed, efficient, and computationally stable. Specifically, by considering the logs of the values of the NH probability mass function (pmf) and then shifting the exponents so that, prior to normalization, the mode acquires a value of 1, concerns for overflow are eliminated.  相似文献   
1000.
Journal of Risk and Uncertainty - We study the impact of new information on people’s perceptions of the risks of e-cigarettes. In September 2019 the U.S. experienced an outbreak of...  相似文献   
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